1. Field of the Invention
The present invention relates to a cable sheath which is used for a cable to be received therein.
2. Description of the Prior Art
Cable sheaths are not only used for a brake cable or the like to be received therein, but protect the cable or users well.
Conventional cable sheath, as shown in U.S. Pat. No. 338,310, includes a plurality of circular tubes which are respectively formed with a tenon on the tube wall. The tubes are connected to one another by the tenons, thereby the bending degree of the cable and the cable sheath are restricted. However, each tube has four tenons, when each tube is connected to one another, many bending directions of the cable sheath would be restricted. When the bending directions and the bending angles of the cable sheath are limited strictly, it would lose the original design purpose of the cable sheath—provide proper bending directions for the cable. Besides, the conventional cable sheath doesn't dispose any fixed structure so that each tube easily slides away from one another.
Another conventional cable sheath, as shown in U.S. Pat. No. 5,933,577, are made of plural main tubes and plural joint tubes in combination. The bending directions of the tubes are restricted by fixed structures on the side of the tubes so that the sheath may bend in only one direction. However, the conventional cable sheath must be made of the main tubes and the joint tubes so as to accomplish the said function; moreover, the whole sheath can be restricted in only one bending direction. Besides, the fixed structures are difficultly dismantled and installed. As above, the conventional cable sheath is inconvenient and lack of variability.
Furthermore, the current merchandises of cable sheaths in the market, including the said prior arts, have a problem in common—the structure of the connecting point of each tube is fragile and easy to be damaged by external force. The conventional cable sheaths don't have any structure can protect the connecting point from being damaged so as to cause their life to be shortened and substitute for a new one often. In other words, all prior arts can't provide a good stability of use.
In addition, when the brake cable is actually received in the cable sheath, in other to the brake cable may bend smoothly, some parts of the brake cable usually require larger space for bending, while the others don't have too many curves. However, the said prior arts don't enable the users to determine the bending sections of the cable sheath for the brake cable as needed.